Description

If you log in as root with the Bourne shell (/bin/sh)
and run asadmin commands, then log out of the console window,
all the domain administration server (DAS), node agent, and instance processes
are killed. This is because in the Bourne shell all child terminals inherit
the TTY by default, so when the terminal is logged out, all child processes
are killed too.

Solution

Before running any asadmin commands, do the following:

Log in to the server.

Change to K shell:

# exec /bin/ksh

In K shell, run all the asadmin commands
to bring up the DAS, node agents, and instances.